Hector joined the Blues in 2015 but has yet to make a first-team appearance and spent the last two seasons on loan with boyhood club Reading and German side Eintracht Frankfurt.
"When I found out that Hull were interested in taking me on loan, it was an easy decision to make," the Jamaica international told hullcitytigers.com.
"It's a great challenge for me to come back to England after a season in Germany and to try and help this club get back into the Premier League.
"The players here seem like a great bunch and hopefully I can play my part in helping them - and the club - enjoy a successful season in 2017-18."
The 25-year-old becomes Hull's fifth summer signing following the arrivals of Ola Aina, Fraizer Campbell, Kevin Stewart and Ondrej Mazuch.